Write a two-column proof.
Given: 7y = 8x – 14; y = 6
Prove: x = 7
1. 7y = 8x – 14 Given
2. y = 6 Given
3. 7(6) = 8x – 14 Substitution of 2 into 1
4. 42 = 8x - 14 Simplification of 3
5. 56 = 8x Addition Property of Equality
6. 7 = x Division Property of Equality
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